arch/sh/kernel/idle.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * The idle loop for all SuperH platforms.
   4  *
   5  *  Copyright (C) 2002 - 2009  Paul Mundt
   6  */
   7 #include <linux/module.h>
   8 #include <linux/init.h>
   9 #include <linux/mm.h>
  10 #include <linux/pm.h>
  11 #include <linux/tick.h>
  12 #include <linux/preempt.h>
  13 #include <linux/thread_info.h>
  14 #include <linux/irqflags.h>
  15 #include <linux/smp.h>
  16 #include <linux/atomic.h>
  17 #include <asm/smp.h>
  18 #include <asm/bl_bit.h>
  19
  20 static void (*sh_idle)(void);
  21
  22 void default_idle(void)
  23 {
  24         set_bl_bit();
  25         raw_local_irq_enable();
  26         /* Isn't this racy ? */
  27         cpu_sleep();
  28         clear_bl_bit();
  29 }
  30
  31 void arch_cpu_idle_dead(void)
  32 {
  33         play_dead();
  34 }
  35
  36 void arch_cpu_idle(void)
  37 {
  38         sh_idle();
  39 }
  40
  41 void __init select_idle_routine(void)
  42 {
  43         /*
  44          * If a platform has set its own idle routine, leave it alone.
  45          */
  46         if (!sh_idle)
  47                 sh_idle = default_idle;
  48 }
  49
  50 void stop_this_cpu(void *unused)
  51 {
  52         local_irq_disable();
  53         set_cpu_online(smp_processor_id(), false);
  54
  55         for (;;)
  56                 cpu_sleep();
  57 }